Serum concentrations of lipopolysaccharide activity-modulating proteins during tuberculosis

Lipopolysaccharide (LPS) is the principal stimulator of host defense against gram-negative bacteria. LPS-binding protein (LBP), bactericidal/permeability-increasing protein (BPI), and soluble CD14 (sCD14) bind LPS and regulate its toxicity. Lipoarabinomannan, a cell wall component of Mycobacterium tuberculosis, resembles LPS with respect to induction of inflammatory responses through recognition by LBP and sCD14. LBP, BPI, and sCD14 were measured in serum of 124 patients with tuberculosis in various stages of disease, in persons who had been in close contact with patients with contagious pulmonary tuberculosis, and in healthy controls. Levels of these LPS toxicity-regulating proteins were elevated in patients with active tuberculosis compared with those in contacts and controls and declined during treatment. The levels of LBP and sCD14 were higher in patients with fever and anorexia. LPS-regulating proteins may play a role in host defense during tuberculosis, presumably through interaction with lipoarabinomannan.     

Pharmacokinetics of cefamandole in patients undergoing hemodialysis and peritoneal dialysis

The pharmacokinetics of cefamandole nafate, a new parenteral cephalosporin derivative, were evaluated in 11 patients with chronic renal failure (creatinine clearance less than 5 ml/min), including five patients during hemodialysis, four patients during routine peritoneal dialysis, and two patients during the interdialytic period. Peak serum levels of cefamandole were comparable to those observed in patients with normal renal function. Clearance of the drug during the interdialytic period and during hemodialysis and peritoneal dialysis was minimal, with a resultant significant prolongation of serum half-life. The nondialyzability of cefamandole is in contrast with reported studies of cephalothin, where significant reduction of the serum half-life was achieved during hemodialysis but not peritoneal dialysis. The concentration of cefamandole in the peritoneal dialysate after parenteral administration was observed to be bactericidal for many gram-negative pathogens and, with the exception of Streptococcus faecalis, most gram-positive organisms found in bacterial peritonitis in patients with severe renal failure. The present data suggest that if stable bactericidal serum levels of cefamandole are to be maintained during hemodialysis and peritoneal dialysis, a parenteral loading dose must be administered followed by one-half the loading dose every half-life.     

Peritonitis in peritoneal dialysis patients after renal transplantation

BACKGROUND: The occurrence of peritonitis in peritoneal dialysis patients after renal transplantation during immunosuppression might increase morbidity and mortality. Hence the timing of catheter removal is still controversial. The associated risk factors of this complication have not been analyzed. METHODS: We analyzed, retrospectively, the incidence of peritonitis within 90 days after transplantation, its associated morbidity and mortality, as well as risk factors. From 1980 until March 1995, 238 consecutive kidney transplants in peritoneal dialysis patients were performed. Univariate and multivariated logistic regression analysis were used to identify risk factors for the development of peritonitis. RESULTS: 232 cases (141 men, 91 women) were available for analysis. In 191 patients, the catheter was removed with a mean interval after transplantation of 122 days (range 0-573). Thirty peritonitis episodes with predominantly Staphylococcus aureus (10/30) or gram-negative bacteria (12/30) were observed. Independent risk factors before transplantation were the total number of peritonitis episodes (P<10(-5)), previous peritonitis with S. aureus bacteria (P<10(-5)), and male sex (P<0.004). Risk factors after transplantation were technical surgical problems (P<10(-5)), more than two rejection episodes (P<0.02), permanent graft nonfunction (P<0.026), and urinary leakage (P<0.035). CONCLUSIONS: Transplantation without simultaneous peritoneal catheter removal is feasible. However, this increases the risk of peritonitis after transplantation. Early catheter removal should be considered seriously in those patients at risk. When peritonitis develops, antibiotic treatment should be directed against gram-positive as well as gram-negative bacteria until culture results are available.     

Resistance to lipopolysaccharide mediated by the Yersinia pestis V antigen-polyhistidine fusion peptide: amplification of interleukin-10

We previously showed that injection of homogenous staphylococcal protein A-V antigen fusion peptide into mice delayed allograft rejection and suppressed the major proinflammatory cytokines tumor necrosis factor alpha (TNF-alpha) and gamma interferon (IFN-gamma) associated with generation of protective granulomas. This study was undertaken to determine if V antigen could prevent endotoxic shock, known to be mediated by excessive production of certain proinflammatory cytokines. After treatment with 50 microg of homogeneous V antigen-polyhistidine fusion peptide (Vh), the 50% lethal dose of purified lipopolysaccharide (LPS) in BALB/c mice immediately rose from 63 microg (normal controls) to 318 microg, fell to near baseline (71 microg) in 6 h, and then slowly rose to a maximum of 566 microg at 48 h before again returning to normal. Injected Vh alone (50 microg) promptly induced the anti-inflammatory cytokine interleukin-10 (IL-10) as well as modest levels of TNF-alpha (an inducer of IL-10) in spleen. Concomitant injection of Vh and an otherwise lethal dose of LPS (200 microg) dramatically decreased levels of TNF-alpha and IFN-gamma in the spleen and peritoneal lavage fluid as compared to values determined for LPS alone. These results would be expected if V antigen directly up-regulated IL-10 that is reported to generally down-regulate proinflammatory cytokines. Mice receiving 200 microg of LPS 48 h after injection of Vh exhibited patterns of cytokine synthesis similar to those observed in endotoxin-tolerant mice, a condition also reported to be mediated by IL-10. These findings suggest that V antigen serves as a virulence factor by amplifying IL-10, thereby repressing proinflammatory cytokines required for expression of cell-mediated immunity.     

Intermittent intraperitoneal ceftazidime dosing in end-stage renal disease

Infections are a common problem in dialysis patients. As hospital stay shortens, many require outpatient antibiotic therapy. Parenteral administration may pose considerable logistic and financial burdens, whereas daily intraperitoneal dosing increases the risk of contamination. Ceftazidime, with its long half-life, may provide adequate dosing when administered intraperitoneally thrice weekly. The authors therefore studied the kinetics of a 2 g loading dose followed by a 1.5 g dose every 48 hr in seven stable chronic peritoneal dialysis patients. In vitro stability at 4 degrees C (measured by high performance liquid chromatography) was 91% at 120 hr. Peak serum concentration (60 +/- 22 microg/ml) was reached at 4.9 +/- 2.2 hr. Serum values were 25 +/- 9 and 8 +/- 3 microg/ml at 24 and 48 hr, respectively. However, median trough levels at 48 hr in dialysate were significantly lower than in serum (2.8 vs 8.5 microg/ml, respectively; p = 0.0425). Pharmacokinetic parameters were as follows: bioavailability (F), 88% +/- 8%; volume of distribution at steady state (VDss), 20 +/- 8 L; absorption half-life (T1/2(abs)), 1.8 +/- 1.3 hr; elimination half-life (T1/2(el)), 11.4 +/- 4.5 hr; and clearance (CL), 22 +/- 10 ml/min. Intraperitoneal ceftazidime every 48 hr is a practical alternative to parenteral therapy of nonperitoneal infections. In peritonitis, whether increased permeability results in improved dialysate levels remains to be defined.     

Pharmacokinetics and bactericidal activity of a single daily dose of netilmicin in the treatment of CAPD-associated peritonitis

Single daily dosage of netilmicin is generally accepted in systemic infections, due to biphasic bactericidal activity and prolonged postantibiotic effect of aminoglycosides. Since little is known about the efficacy of single daily intraperitoneal application of netilmicin in the treatment of CAPD-associated peritonitis, we conducted this prospective study. Seven patients with CAPD-associated peritonitis were treated with a single daily dose of netilmicin (loading dose 1.5 mg/kg, followed by 40 mg/21 bag/day). Serum and intraperitoneal levels as well as bactericidal activity of netilmicin against Acinetobacter baumanii, E. coli and Pseudomonas aeruginosa were measured for 48 hours. Serum and peritoneal levels widely varied among the patients due to different interindividual plasma clearance of netilmicin. The intraperitoneal antibacterial action of netilmicin was decreased, more over, substantial differences in the bactericidal activity were found among the patients. However, with high initial netilmicin levels sufficient bactericidal activity was found for Acinetobacter and E. coli, but not for Pseudomonas aeruginosa. Hence, a single daily dosage of netilmicin can be a suitable treatment of CAPD-associated peritonitis, only if the dose is adapted according to the first serum and peritoneal levels. In infections with Pseudomonas aeruginosa higher peritoneal levels of netilmicin and the combination with other antibiotics will be needed for a sufficient peritoneal bactericidal activity.     

Relationship between soluble CD14, lipopolysaccharide binding protein, and the alveolar inflammatory response in patients with acute respiratory distress syndrome

The effects of bacterial endotoxin (lipopolysaccharide, LPS) are amplified by lipopolysaccharide binding protein (LBP) and CD14, resulting in cellular activation at very low concentrations of LPS. To investigate the importance of this pathway in acute lung injury, we measured LPS, LBP, and soluble CD14 (sCD14) in the bronchoalveolar lavage fluid (BAL) of 82 patients with acute respiratory distress syndrome (ARDS). LBP and sCD14 increased markedly in BAL of patients with ARDS. sCD14 and LBP each were strongly related to BAL total protein and polymorphonuclear neutrophil (PMN) concentration, whereas LPS concentration was not. Multivariate analyses showed sCD14 to be strongly related to BAL total protein, even after controlling for LPS and LBP concentrations. sCD14 was strongly and independently related to PMN concentration, after controlling for BAL LPS, LBP, and interleukin-8 (IL-8). The BAL LPS concentration was not strongly related to either BAL total protein or BAL PMN. The BAL sCD14 and LBP values were similar in all subgroups of patients with ARDS, and were not related to survival. The serum LBP and sCD14 were elevated in ARDS, but were not related to BAL total protein, LBP, sCD14, PMN, or clinical outcome. Thus, LBP and sCD14 reach high concentrations in the lungs of patients with ARDS, and BAL sCD14 is strongly related to two major indices of lung inflammation: total protein and PMN concentration. CD14-dependent mechanisms may contribute to lung inflammation in ARDS.     

Interleukin-8 in chronic renal failure and dialysis patients

A total of 105 patients participated in this study, including 10 with chronic glomerulonephritis with normal renal function (CGN patients), 36 uraemic patients (CRF patients), 19 continuous ambulatory peritoneal dialysis patients (CAPD) without peritonitis, three CAPD patients with peritonitis, 37 patients undergoing chronic haemodialysis (HD) divided into short-term HD, 15 patients; medium-term HD, 12 patients; and long-term HD, 10 patients. IL-8 and two other proinflammatory cytokines, IL-6 and TNF alpha were tested using a specific immunoassay. IL-8, IL-6, and TNF alpha serum levels were significantly increased in patients with chronic renal failure compared to their levels in normal individuals (P < 0.0001, P < 0.05 and P < 0.0001 respectively). The most pronounced increment in IL-8, IL-6 and TNF alpha serum levels was observed in CAPD patients (P < 0.0001). CAPD patients without peritonitis showed relatively low levels of IL-8 or IL-6 in peritoneal dialysate effluents (PDE), whereas PDE-TNF alpha were not detectable in almost all patients tested. Patients with peritonitis showed very high serum and PDE levels of IL-8, IL-6 and TNF alpha. The clinical recovery from peritonitis was characterized by a rapid fall in IL-8, IL-6 and TNF alpha in serum and dialysate. HD patients showed a significant increase in serum levels of IL-8 and also IL-6 and TNF alpha compared to normal individuals (P < 0.05, P < 0.05 and P < 0.01 respectively).(ABSTRACT TRUNCATED AT 250 WORDS)     

Chronic sinusitis refractory to standard management in patients with humoral immunodeficiencies

Chronic refractory sinusitis is a common feature in patients with primary immunodeficiencies. The efficacy of standard therapeutic strategies is questionable. In an open trial we evaluated the efficacy of azithromycin, N-acetylcysteine and topical intranasal beclomethasone (100 microg twice daily for 6 weeks) in 16 patients with primary immunodeficiencies (median age 13.5 years, range 5-32 years). All patients suffered from chronic sinusitis despite regular immunoglobulin replacement therapy every 3 weeks. Magnetic resonance imaging (MRI) scans were performed before and after 6 weeks of treatment to evaluate morphological changes in the paranasal sinuses. Nasal swabs and washings were taken for microbial analysis and measurement of inflammatory mediators (IL-8, tumour necrosis factor-alpha (TNF-alpha), eosinophilic cationic protein (ECP)) before and post therapy. Inflammatory mediators in nasal secretions were significantly elevated in patients: IL-8 median 2436 pg/ml (range 441-5435 pg/ml), TNF-alpha 37.3 pg/ml (3.75-524 pg/ml) and ECP 33 ng/ml (1.5-250 ng/ml) versus age-matched healthy controls: IL-8 median 212 pg/ml (99-825 pg/ml), TNF-alpha 3.77 pg/ml (2.8-10.2 pg/ml) and ECP 1.5 ng/ml (1.5-14.8 ng/ml) (P < 0.0001). Inflammation of the maxillary sinuses was confirmed by MRI scans in all patients, additionally infection of the ethmoidal and frontal sinuses was recorded in five patients. Bacterial growth appeared in 11 out of 16 cultures. In spite of therapy, no improvement in sinal inflammation visualized by MRI was achieved. Moreover, no significant decrease in pathogens and levels of inflammatory mediators could be detected (IL-8 1141 pg/ml, 426-4556 pg/ml; TNF-alpha 13.9 pg/ml, 4.1-291.6 pg/ml; ECP 32.3 ng/ml, 3.7-58.4 ng/ml). Our results demonstrate that conventional management of sinusitis is of little benefit in patients with chronic refractory sinusitis with an underlying immunodeficiency. More studies are needed to test antibiotic regimens, probably combined with surgical drainage and anti-inflammatory agents.     

Clinical significance of serum cytokine patterns during start of fever in patients with neutropenia

Serum concentrations of tumour necrosis factor alpha (TNF-alpha), interleukin-1 receptor antagonist (IL-1ra), interferon gamma (IFN-gamma), interleukin-6 (IL-6) and interleukin-10 (IL-10) were studied in 31 patients with haematological malignancies during febrile neutropenia. Samples were obtained when blood cultures were performed (time 0) and, when possible, after 2, 4, 6, 12 and 24 h. Increased levels of all cytokines were detected after start of fever with peak values in gram-negative (Gr-) bacteraemias after 2 h (TNF-alpha, IL-1ra and IFN-gamma), 4 h (IL-6) and 6 h (IL-10), respectively. At time 0 the median TNF-alpha value was higher in the Gr- group (80 pg/ml; range 54-516 pg/ml) as compared to both gram-positive bacteraemias (Gr+, 14 pg/ml; range 7-60 pg/ml; P < 0.05) and blood culture negative episodes (BCN, 8 pg/ml; range 0-87 pg/ml; P < 0.05). Furthermore, the peak values of TNF-alpha, IL-1ra, IL-6 and IL-10 during the 24 h study period were significantly and/or numerically higher in the Gr- group in comparison to the Gr+ and BCN groups, respectively. It may be concluded that neutropenic patients have increased levels of both pro- and anti-inflammatory cytokines at start of fever, with the highest values recorded during the first hours in Gr- bacteraemias. Prospective studies will show whether monitoring of serum cytokines may be used as an early diagnostic tool before results of blood cultures are available, which may have important therapeutic implications.     

Oral ganciclovir dosing in transplant recipients and dialysis patients based on renal function

BACKGROUND: An oral formulation of ganciclovir (GCV) was recently approved for the prevention of cytomegalovirus disease in solid organ transplant recipients. This study was designed to determine the bioavailability of GCV and to test a dosing algorithm in transplant and dialysis patients with different levels of renal function. METHODS: Pharmacokinetic studies were carried out in 23 patients who were either a recipient of an organ transplant or on hemodialysis. Drug dosing was established by the following algorithm based on calculated creatinine clearance (CrCl): CrCl = [(140-age) x body weight]/(72 x Cr) x 0.85 for women that is, CrCl >50 ml/min, 1000 mg every 8 hr; CrCl of 25-50 ml/min, 1000 mg every 24 hr; CrCl of 10-24 ml/ min, 500 mg every day; CrCl < 10 ml/min (or on dialysis), 500 mg every other day after dialysis. GCV was taken within 30 min after a meal. The patients received oral GCV for between 12 days and 14 weeks. Serum specimens (or plasma from patients on hemodialysis) obtained at steady state were analyzed for GCV concentrations by high-performance liquid chromatography. In nine of the transplant recipients, absolute bioavailability was determined by comparing GCV levels after single oral and intravenous doses of GCV. RESULTS: The following GCV concentrations (mean +/-SD) were determined: with CrCl of > or =70 ml/min, the minimum steady-state concentration (Cmin) and maximum concentration (Cmax) were 0.78+/-0.46 microg/ml and 1.42+/-0.37 microg/ml, respectively, with a 24-hr area under the concentration time curve (AUC0-24) of 24.7+/-7.8 microg x hr/ml; with CrCl of 50-69 ml/min, the Cmin and Cmax were 1.93+/-0.48 and 2.57+/-0.39 microg/ml, respectively, with an AUC0-24 of 52.1+/-10.1 microg x hr/ml; with CrCl of 25-50 ml/min, the Cmin and Cmax were 0.41+/-0.27 and 1.17+/-0.32 microg/ml, respectively, with an AUC0-24 of 14.6+/-7.4 microg x hr/ml. For one patient with a CrCl of 23.8 ml/min, the Cmin and Cmax were 0.32 and 0.7 microg/ml, respectively, with an AUC0-24 of 10.7 microg x hr/ml. With CrCl of <10 ml/min, the mean Cmin and Cmax were 0.75+/-0.42 and 1.59+/-0.55 microg/ml, respectively, with a mean AUC0-24 of 64.6+/-18.8 microg x hr/ml. Absolute bioavailability, for the nine patients so analyzed, was 7.2+/-2.4%. For those patients with end-stage renal failure, GCV concentrations fell during dialysis from a mean of 1.47+/-0.48 microg/ml before dialysis to 0.69+/-0.38 microg/ml after dialysis. CONCLUSIONS: The bioavailability of oral GCV in transplant patients was similar to that observed in human immunodeficiency virus-infected patients. However, levels between 0.5 and 1 microg/ml (within the IC50 of most cytomegalovirus isolates) could be achieved with tolerable oral doses. The proposed dosing algorithm resulted in adequate levels for patients with CrCl greater than 50 ml/min and for patients on dialysis. For patients with CrCl between 10 and 50 ml/min, the levels achieved were low and these patients would likely benefit from increased doses.     

Soluble CD14(1-152) confers responsiveness to both lipoarabinomannan and lipopolysaccharide in a novel HL-60 cell bioassay

CD14 is a pattern recognition receptor involved in the interaction with multiple ligands, including LPS from gram-negative bacteria and lipoarabinomannan (LAM) from mycobacteria. While the interactions between LPS and soluble CD14 (sCD14) have been analyzed in detail, LAM/CD14 interactions remain uncharacterized due to the lack of suitable functional assays. We describe herein a novel bioassay for the analysis of CD14/ligand interactions. CD14-negative myeloid HL-60 cells up-regulate endogenous CD14 gene expression when stimulated with LPS in the presence of recombinant soluble CD14(1-348). Using the HL-60 bioassay, we showed that sCD14(1-348) confers responsiveness not only to LPS, but also to LAM. The response to LAM, but not that to LPS, was highly dependent on LPS binding protein (LBP). The N-terminal half of CD14 was sufficient to mediate HL-60 responses to LAM, since HL-60 cells responded with similar efficiency when stimulated with LAM and LBP in the presence of sCD14(1-348) or sCD14(1-152). Thus, the N-terminal 152 amino acids of CD14 contain the site(s) involved in the interaction with LAM and LBP, as well as the residues required for LAM-dependent CD14 signaling.     

Serum levels of interleukin 1 and tumor necrosis factor alpha correlate with peritoneal adhesion grades in humans after major abdominal surgery

Peritoneal adhesions are a leading cause of potential morbidity and mortality. We undertook this prospective study to determine the clinical relevance of interleukin 1 (IL-1) and tumor necrosis factor alpha (TNF-alpha) levels as biological markers for peritoneal adhesion formation in humans. Fifteen patients who had previous colectomies and were undergoing re-exploration for an elective vascular procedure were studied. Blood samples were collected from each patient preoperatively and 30 minutes after the abdominal incision was made. Serum levels of IL-1 and TNF-alpha were determined using enzyme-linked immunosorbent assay kits. Adhesions were graded using an adhesion scale of 0 (none), 1 (mild), 2 (moderate), and 3 (extensive, dense). Preoperative levels of IL-1 and TNF-alpha did not differ significantly among all patients (IL-1 level was 60 +/- 14 pg/mL, and TNF-alpha level was 45 +/- 11 pg/mL; mean +/- standard deviation). Significant correlation was observed between grades of adhesions and early intraoperative levels of IL-1 [101 +/- 36 pg/mL for grade 1 (n = 8) vs 298 +/- 73 pg/mL for grade 3 (n = 6); P < 0.01] and TNF-alpha (88 +/- 23 pg/mL for grade 1 vs 261 +/- 88 mL for grade 3; P < 0.02). We conclude that early elevations of IL-1 and TNF-alpha are reliable biological markers for postoperative adhesions in humans. Studies utilizing cytokines antibodies to these markers may further elucidate the efficacy of this method for prevention of peritoneal adhesions.     

The epidemiology of peritonitis in acute peritoneal dialysis: a comparison between open- and closed-drainage systems

We performed a prospective study to examine the epidemiology and microbiology of peritonitis complicating acute intermittent peritoneal dialysis (IPD) performed in an in-hospital setting for the management of acute and chronic renal failure and to see the effect of a closed-drainage system on altering the frequency and cause of peritonitis. Over a 15-month period, 79 patients were treated with acute IPD for a total of 136 treatments each ranging in length from 2 to 40 days (median, 4 days). The majority of cases had acute renal failure (ARF; 65%) and were treated in intensive care units (ICUs; 74%) with serious comorbid conditions (60%). About half were treated with a two-bag, ventable (open)-drainage system with unprotected spikes, and the other half were treated with a single-bag, spike-protected, closed-drainage system. There were 27 cases of peritonitis for a rate of 4.5 cases/100 patient-days at risk. About half were gram-positive infections; the remainder were gram-negative or mixed (25%) or Candida sp (25%). The use of a closed-drainage system reduced the incidence of system-related peritonitis from 3.6 to 1.5 cases/100 patient-days. There was a high rate of peritonitis in the first 48 hours of treatment, which fell to a low stable rate thereafter and remained so for up to 15 days of continuous IPD. The use of a closed-drainage system eliminated the early (< 48 hours) high rate of peritonitis and maintained a low constant rate of peritonitis throughout treatment. There was an association of ARF and severe comorbid disease with more virulent organisms (gram-negative, mixed, and Candida sp), which, in turn, were both associated with antecedent broad-spectrum antibiotic therapy. Random positive surveillance cultures showed a frequency distribution similar to that of peritonitis cases over the duration of treatment, but with less virulent organisms. Peritonitis in acute IPD occurs when large or repeated inocula of organisms from the prevailing flora overwhelm the peritoneal immune clearance mechanisms. Prolonged courses of broad-spectrum antibiotic therapy provide no protection, but shift the resulting infecting flora toward more virulent pathogens. A closed-drainage system provides one method to reduce the frequency of peritoneal contamination.     

Anorexigen (TNF-alpha, cholecystokinin) and orexigen (neuropeptide Y) plasma levels in peritoneal dialysis (PD) patients: their relationship with nutritional parameters

BACKGROUND: Malnutrition has definitely been related to mortality among dialysis patients. Persistent loss of appetite is one of the major symptoms found in these patients. It is also well recognized that several substances produce anorexia or disorders of the hunger-satiety cycle in several diseases. The aim of this study was to identify the role of anorexigen substances (TNF-alpha and cholecystokinin or CCK) and an orexigen substance (neuropeptide Y or NPY) in anorexia and malnutrition among 55 clinically stable peritoneal dialysis (PD) patients. RESULTS: High TNF-alpha plasma levels were found in 41 of 42 patients (97.6%) with a mean of 70.5+/-32.3 pg/ml. Patients with anorexia (n=11) or anorexia with nausea or vomiting (n=5) had higher TNF-alpha values than patients without these symptoms (75.9+/-34 vs 52.1 +/-24.5 pg/ml, P<0.05). Eight patients with a prior diagnosis of acid pylori disease showed higher TNF-alpha values (87.2+/-24.3) than 30 unaffected patients (63.6+/-30.5, P<0.05). TNF-alpha showed a significant negative linear correlation with retinol binding protein (RBP) (r=-0.37, n=34, P<0.05), and venous pH (r=-0.4, n=42, P<0.01); also, TNF-alpha values higher than 65 pg/ml were inversely associated with transferrin, cholesterol, blood urea nitrogen (BUN) and CCK. Patients with prealbumin levels lower than 30 mg/dl, a BMI lower than 30 kg/m2, nPCR lower than 1.1 g/kg/day and urea KT/V lower than 2.2 showed higher serum TNF-alpha levels. Patients who had been on CAPD treatment for longer periods showed higher TNF-alpha values. High plasma CCK levels were found in 38 of 45 patients (84%), mean 45.9+/-32.3 pg/ml. Patients with anorexia had no difference in CCK values compared with those without. A direct association was found between CCK levels and some nutritional markers (albumin, fibronectin, triglycerides, folic acid and nPCR in non diabetic patients). Although CCK has a recognized anorectic effect, this direct association might be because of an abnormal stimulation of CCK glucose feedback (trypsin) due to continuous peritoneal glucose absorption. This suggests that CCK could be an immediate food intake marker in PD patients. The NPY plasma levels were normal in 33 patients, high in 6 and low in 11. Patients with anorexia showed lower NPY levels than those without. NPY values greater than 50 pg/ml were directly associated with higher transferrin, prealbumin, RBP, nPCR and urea KT/V values. Importantly, a negative linear correlation between NPY and TNF-alpha was found (r=-0.42, n= 41, P<0.01). There was no significant relationship between residual renal clearance and the serum levels of the three peptides. CONCLUSION: In conclusion, our data suggest that high TNF-alpha and low NPY serum levels are associated with anorexia. High TNF-alpha, low CCK and low NPY serum levels are also related to a poor nutritional status. Further research on these circulating substances is required.     

Soluble CD14 activates monocytic cells independently of lipopolysaccharide

The glycoprotein CD14 acts as a receptor for lipopolysaccharide (LPS), either when anchored in the myeloid cell membrane (mCD14) or as a soluble molecule (sCD14) in serum. sCD14-LPS complexes activate cells devoid of mCD14. However, the role of sCD14 independent of LPS is unknown. Therefore, the effect of sCD14 on monocyte functions was investigated in the monocytic cell lines THP1 and Mono Mac 6 and in fresh human monocytes. Under serum-free conditions, endotoxin-free human recombinant sCD14(1-348), (rsCD14(1-348)) induced tumor necrosis factor alpha (TNF-alpha). The TNF-alpha effect was stronger in THP1 cells than in Mono Mac 6 cells or monocytes. It was dose dependent, with a maximum at 1 microg/ml, and time dependent, with a maximum after 2 h. sCD14 purified from urine had the same cytokine-activating capacity. In contrast, C-terminally truncated rsCD14(1-152) was inactive. The rsCD14 effect was not due to LPS contamination, since it was resistant to polymyxin and lipid IVa but sensitive to heat and trypsin. The rsCD14-induced cytokine induction was blocked by preincubation of rsCD14 with a monoclonal anti-CD14 antibody that did not recognize the LPS-binding site. Release of the TNF-alpha disappeared upon pretreatment of rsCD14 in 50% plasma or in complete, heat-inactivated or sCD14-depleted serum. Moreover, cytokine production was no longer observed when rsCD14 was pretreated with thrombocytes. The thrombocyte effect was dose and time dependent. In conclusion, sCD14 is able to activate myeloid cells, and the effect is prevented by the presence of plasma, serum, or thrombocytes.     

Changes in bone turnover markers and menstrual function after short-term oral DHEA in young women with anorexia nervosa

Intermittent intraperitoneal antibiotic administration appears as a practical and economical therapeutic concept in continuous peritoneal dialysis (CPD)-related peritonitis, but the equivalence of this principle with standard continuous treatment awaits confirmation by prospective, randomized clinical trials. This study evaluates the efficacy, safety, and clinical acceptance of an initial combination treatment including a glycopeptide (vancomycin or teicoplanin) and ceftazidime, each applied either intermittently or continuously, in a cohort of pediatric patients with CPD-related peritonitis. Patients randomized for continuous treatment received an intraperitoneal loading dose of glycopeptide and ceftazidime followed by maintenance doses added to each dialysate bag. In the intermittent treatment groups, the glycopeptide was administered in two loading doses 7 d apart, and ceftazidime during one dialysis cycle per day. Initial treatment response was evaluated after 60 h by the change in a Disease Severity Score and by the clinical decision to continue initial treatment. Of 152 patients observed for a total of 234 patient years, 90 patients developed 195 episodes of peritonitis (including 27 relapses within 4 wk after end of treatment). Dialysate cultures were positive in 83% of the episodes. In gram-positive peritonitis (79% of culture-positive cases), the primary success (overall 95%) and relapse rates (21%) were not different between continuous and intermittent, or between vancomycin and teicoplanin treatment. Oversensitivity reactions occurred in three and ototoxicity in one vancomycin-treated patient, whereas no such side effects were observed with teicoplanin. Residual renal function declined during peritonitis episodes regardless of treatment modality. In gram-negative peritonitis (18% of cases), intermittent ceftazidime treatment was less successful than continuous treatment according to clinical judgment (3 of 11 versus 10 of 14, P < 0.05), but not when rated by Disease Severity Score (8 of 11 versus 12 of 14). In conclusion, intermittent and continuous intraperitoneal treatment of CPD-related peritonitis with glycopeptides and ceftazidime is equally efficacious and safe when measured by objective clinical criteria. This contrasts with a strong tendency of clinicians to move from intermittent to continuous treatment in severe peritonitis.     

Synchrony in telomere length of the human fetus

We measured serum tumour necrosis factor-alpha (TNF-alpha) as well as interleukin-1betta (IL-1beta) and GH concentrations in 15 children with isolated growth hormone deficiency (GHD), age range 5.1-13.9 years, before and 4 and 24h after the first GH injection (0.1 IU/kg s.c.). No differences were found in basal concentrations of serum TNF-alpha and IL-1beta between GHD children (10.01 +/- 1.55 pg/ml and 2.14 +/- .16 ng/ml respectively) and sex- and age-matched controls (11.57 +/- 2.16 pg/ml and 3.78 +/- 1.46 ng/ml respectively). In GHD children, serum TNF-alpha and IL-1beta values had significantly increased (P < 0.002) 4h (26.75 +/- 5.57 pg/ml and 2.99 +/- 0.21 ng/ml respectively) and decreased again 24 h after GH administration. Likewise, serum GH levels had significantly increased 4 h (from 1.29 +/- 0.69 to 48.71 +/- 13.35 ng/ml, P < 0.001) and decreased to basal values 24h after GH administration. A significant correlation was found between basal serum concentrations of GH and those of both TNF-alpha (P < 0.01) and IL-1beta (P < 0.05). However, no correlation was found between serum GH concentration and either TNF-alpha or IL-1beta levels 4 and 24h after GH administration. Our data suggest that GH plays a role in modulating TNF-alpha and IL-1beta release in humans.     

Leukocyte migration across human peritoneal mesothelial cells is dependent on directed chemokine secretion and ICAM-1 expression

BACKGROUND: Leukocyte migration into the peritoneal cavity is a diagnostic feature of peritonitis in patients treated with peritoneal dialysis (PD). While neutrophil (PMN) influx is characteristic of the acute phase of peritoneal infection, significant mononuclear cell (MNC) infiltration, occurs throughout the whole period of infection. Recent data suggests that human peritoneal mesothelial cell (HPMC) adhesion molecule expression and the synthesis of chemotactic cytokines may be important in the process. METHODS: In the present study we have examined, the regulation and directed secretion of chemokines (IL-8, MCP-1 and RANTES) and the basolateral to apical migration of unstimulated leukocytes across mesothelial cell monolayers using an in vitro model where HPMC were grown on the porous membrane of tissue culture inserts. Separate experiments have defined the importance of chemokine synthesis and ICAM-1 expression in the transmigration process. RESULTS: Apical stimulation of HPMC with IL-1 beta or TNF alpha resulted in a time and dose dependent up-regulation of IL-8, MCP-1 and RANTES mRNA expression and synthesis. This secretion was predominately into the apical compartment (> 85%) with all chemokines. Apical pre-stimulation of HPMC resulted in a dose- and time-dependent migration of both PMN and MNC across HPMC. Neutrophil migration was significantly reduced in the presence of appropriate concentrations of polyclonal IL-8 antibody (IL-1 beta (100 pg/ml) 153 +/- 12 versus anti-IL-8 (100 ng/ml) 71 +/- 7 (X 10(3)) PMN, N = 6, P < 0.02) and in the presence of anti-ICAM-1 F(ab)'2 fragments or soluble ICAM-1. Constitutive and cytokine stimulated mononuclear cell migration was significantly reduced in the simultaneous presence of polyclonal MCP-1 or RANTES antibody. CONCLUSIONS: These data demonstrate that HPMC synthesize IL-8, MCP-1 and RANTES in response to inflammatory cytokines. HPMC-derived C-x-C and C-C chemokines might contribute to the intra-peritoneal recruitment of leukocytes during peritoneal inflammation.     

Recombinant human erythropoietin resistance in hemodialysis. Effects of paired filtration dialysis

A percentage of hemodialysis (HD) patients are resistant to recombinant human erythropoietin (rHuEPO), a phenomenon that occurs less frequently in patients dialyzed with biocompatible membranes (M) and in peritoneal dialysis. The authors evaluated the effects of paired filtration dialysis (PFD)--a dialysis technique based on the use of an emophan M in conjunction with a polysulphone M--on erythropoiesis in HD patients resistant to rHuEPO. Twelve HD patients with anemia resistant to long-term therapy with rHuEPO (200.24 U/kg body weight three times per week intravenously for 10.2 months) were studied. Patients had been treated for an average of 46.9 months with bicarbonate HD, using cuprophan M (Phase A) and, successively, for 12 months by PFD (Phase B). The following parameters were evaluated monthly: 1) hemoglobin and hematocrit values; 2) serum levels of erythropoietin (EPO); and 3) serum levels of interleukin (IL)-3, IL-6, IL-10, IL-1 beta, tumor necrosis factor alpha (TNF-alpha), and interferon gamma (IFN-gamma). At the end of Phase A and Phase B, patients underwent bone marrow biopsies to evaluate 1) bone marrow burst forming unit erythroid (BFU-E) and colony forming unit erythroid (CFU-E) proliferative capacity, and 2) bone marrow mononuclear cell EPO-receptor (EPO-R) number. During Phase B, there was a progressive rise in hematocrit and hemoglobin values, so that within the sixth month, the rHuEPO dose was reduced to 80 +/- 15 U/kg body weight three times per week. At the same time, an increase in serum IL-3, IL-6, and IL-10 levels was seen, whereas serum IL-1 beta, TNF-alpha, and IFN-gamma levels decreased. This was accompanied by a rise in BFU-E and CFU-E growth and in bone marrow mononuclear cell EPO-R number. During Phase B, after the dialysis session, serum EPO levels increased by about 30% in comparison with pre dialysis values, whereas during Phase A they decreased by about 14%. In HD patients, EPO resistance may caused either by absorption of rHuEPO to the cuprophan M, or an increased release of cytokines that inhibit erythropoiesis, such as IL-1 beta, TNF-alpha, and IFN-gamma, and to a decrease in stimulatory cytokines such as IL-3, IL-6, and IL-10. These negative phenomena are reversed by the use of biocompatible dialysis techniques such as PFD.